Benefit Plans (Fair Value of Plan Assets Measured on a Recurring Basis) (Details) - Fair Value, Recurring - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 963	$ 915
Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	677	618
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	35	57
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	630	548
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	13
Fair Value Measured at Net Asset Value Per Share
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	286	297
Total fixed maturity securities | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	599	540
Total fixed maturity securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Total fixed maturity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	587	527
Total fixed maturity securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	13
Corporate and other bonds | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	477	413
Corporate and other bonds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate and other bonds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	473	408
Corporate and other bonds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	5
States, municipalities and political subdivisions | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	11	6
States, municipalities and political subdivisions | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
States, municipalities and political subdivisions | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	11	6
States, municipalities and political subdivisions | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Asset-backed | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	111	121
Asset-backed | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Asset-backed | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	103	113
Asset-backed | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	8
Equity securities | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	36	23
Equity securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	8
Equity securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	36	15
Equity securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Short-term investments | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	33	47
Short-term investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	33	47
Short-term investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Short-term investments | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Other assets | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	6
Other assets | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Other assets | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	6
Other assets | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash | Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	2
Cash | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	2
Cash | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0